Consider the mystery of the toy train. This industriously chugging mini-locomotive winds its way through “Hero’s Welcome,” Alan Ayckbourn’s 79th (you read that correctly) play, which just opened at 59E59 Theaters as part of the Brits Off Broadway Festival.

In a work that includes all manner of dire deceptions and betrayals, which seem guaranteed to end in tears if not in bloodshed, that little train set — which runs through the entire house of a mayor and her husband — may not seem like such a big deal. But this is a play by Mr. Ayckbourn; nothing is too small to bear revelatory weight.

The toy train and its elaborate accouterments, the pride of a middle-aged man and the despair of his tolerant wife, initially register as the kind of quirky, colorful details with which comic playwrights define their characters. But by the end, this seemingly incidental plaything suggests the full dimensions of a relationship, a tragic chapter in its history and, for one character, a fate that may well be worse than death.

Little things mean a lot in the world of Mr. Ayckbourn, whose “Hero’s Welcome” runs in repertory with his “Confusions,” a bill of linked sketches written 41 years earlier. (Both productions originated at his home base, the Stephen Joseph Theater of Scarborough, England, and are directed by the author.) The wife and husband described above, played by Elizabeth Boag and Russell Dixon, aren’t even the central figures in “Hero’s Welcome.” That would be the hometown hero of the title and his foreign war bride, embodied by Richard Stacey and Evelyn Hoskins.

Yet so deft is Mr. Ayckbourn’s dramatic shorthand that he can summon complete, quirkily detailed back stories for not one but three intersecting couples in a single, standard-length play. He manages to do so while engineering an elaborate plot, as full of twists and secrets as anything by Ibsen, in which everybody lies, including the British government.

Mr. Ayckbourn, 77, has built one of the most prolific and successful careers in British theater on the premise that there are no small parts, in life or onstage. In multiplay masterworks like “The Norman Conquests” and “House and Garden,” he keeps shifting points of view, so that characters hitherto in the background suddenly dominate the foreground. And no matter what their positions on the canvas, these people are usually as sad as they are funny and vice versa.

The zesty appetizers that make up “Confusions” (which despite being one of Mr. Ayckbourn’s most performed works is only now having its New York premiere) demonstrate that this writer’s sensibility was fully formed years ago, when he was a mere stripling of 35. They’re trifles by his later standards, quick-sketch farces programmed to end with zingers.

But these five one-acters also allow you to see clearly the basic building blocks from which Mr. Ayckbourn constructs his more complex works. And even the silliest of them is steeped in the critical yet compassionate sensibility — call it sentimental cynicism — that is uniquely their creator’s.

The best-known of these is the rowdiest, “Gosforth’s Fete,” in which a village fair is leveled by both a thunderstorm and raging human incompetence. My personal favorite is the first on the bill, “Mother Figure,” in which a homebound housewife has become so used to dealing only with her inexhaustible children that she treats any adults who enter her home as if they were toddlers.

Image

From left, Russell Dixon, Charlotte Harwood, Stephen Billington and Richard Stacey in “Confusions,” directed by its author.CreditSara Krulwich/The New York Times

Ms. Boag plays the Mom (pricelessly) in that one, and Charlotte Harwood and Stephen Billington are the couple who live next door. All three show up in different roles in the subsequent playlet, set in a small-town hotel, with Mr. Stacey appearing as the absent father from the first play. Mr. Dixon joins their ranks for the third play, and the entire cast of five is recycled for the evening’s duration.

That’s one of the primary joys of “Confusions,” watching chameleon performers change identities with wigs and accents, while locations are transformed by the rearrangement of simple pieces of furniture. (Michael Holt is the designer.) But there’s also the joy of seeing Mr. Ayckbourn casually play with perspective, as in a restaurant scene in which we hear only what a waiter (Mr. Billington) hears as he moves in and out of earshot between two squabbling tables for two.

“Hero’s Welcome” has no similar antics of technique. Though it is Mr. Ayckbourn’s most recent play, it is also one of this most old-fashioned. This tale of a soldier’s return to the town he left under shady circumstances years earlier has the structure of a 19th-century melodrama in which the sins of the past overtake the placid present.

The plot’s combustible ingredients include a jilted bride, arson, and a vial of tranquilizers and a loaded gun just begging to be picked up. Yet “Hero’s Welcome” remains a comedy, at least in the sense that Chekhov called his plays comedies. Its characters are enjoyably silly in their pretensions and eccentricities. They are also capable of acts of genuine evil and genuine heroism.

“Hero’s Welcome” is a crowded work, and not just because this production crams three detailed playing spaces — which portray the home turf of the play’s three sets of couples — onto a small stage. It has more twists of plot than a season of “Coronation Street.”

But never make the mistake of thinking Mr. Ayckbourn doesn’t know what he’s doing. The dense, teetering structure of “Hero’s Welcome” is dictated by the dense, teetering class structure that still rules and stifles English life.

Now throw an outsider into this insular society, and see if she sinks or swims or makes tidal waves. That’s Madrababacascabuna (the delightful Ms. Hoskins), the young wife of the returning hero, who looks like a natural victim.

Baba, as her husband calls her, doesn’t speak English. Which leads to the expected malapropisms, as when she tells a woman whose house she has just entered, “You have a beautiful hole.” That hostess, a kind soul in a sour marriage, explains, “You’ll find that in our language there’s lots of words than can be taken in different ways.”

Having to deal with all that linguistic nuance can be burdensome, of course, and that’s more or less true of any culture. Mr. Ayckbourn, gentleman that he is, has given Baba a vaguely Eastern European-sounding language he invented just for her.

She approaches a closed world — one in which Mr. Ayckbourn’s characters are usually prisoners for life — with her own set of shiny new tools. That may sound like a handicap. But in “Hero’s Welcome,” it’s the foreign visitor who has the advantage over the old home team that Mr. Ayckbourn has spent his fruitful career coaching into blunders.

Correction:June 21, 2016

A theater review on Thursday about two works by the playwright Alan Ayckbourn now playing in repertory at 59E59 Theaters in Manhattan misstated the amount of time that came between their composition. “Confusions,” a group of linked sketches, was written 41 years before the new play “Hero’s Welcome” — not 30 years. The review also misstated Mr. Ayckbourn’s age at the time he wrote “Confusions.” He was 35, not in his mid-40s.